<template>
    <div>
    <div class="goods">
      <div class="menu-wrapper">
        <ul  class="ulBox" ref='ulBox'>
          <!--current 表示高亮-->
          
           <!-- :class="{current: index===currentIndex}" -->
            <!-- @click="clickMenuItem(index)" -->
              <!-- :class="{current:index===currentIndex}" -->
          <li class="menu-item" v-for="(good, index) in goods" :key="index"
               @click="clickMenuItem(index)"
               :class="{current:index===currentIndex}"
              >
            <span class="text bottom-border-1px">
               <!-- :src="good.icon" v-if="good.icon" -->
              <img class="icon"  :src='good.icon'   v-if="good.icon"> 
              {{good.name}}
            </span>
          </li>
        </ul>
      </div>
      <div class="foods-wrapper">
        <ul ref="foodsUl" class="foodsUl">
          <li class="food-list-hook" v-for="(good, index) in goods" :key="index">
            <h1 class="title">{{good.name}}</h1>
            <ul>
               <!-- @click="showFood(food)" -->
                
                  <!-- @click="showFood(food)" -->
              <li class="food-item bottom-border-1px" v-for="(food, index) in good.foods"
                  :key="index" 
                 
                  
                  >
                <div class="icon">
                  <img width="57" height="57" :src="food.icon">
                </div>
                <div class="content">
                  <h2 class="name">{{food.name}}</h2>
                  <p class="desc">{{food.description}}</p>
                  <div class="extra">
                    <span class="count">月售{{food.sellCount}}份</span>
                    <span>好评率{{food.rating}}%</span>
                  </div>
                  <div class="price">
                    <span class="now">￥{{food.price}}</span>
                    <!-- <span class="old" v-if="food.oldPrice">￥{{food.oldPrice}}</span> -->
                  </div>
                  <div class="cartcontrol-wrapper">
                   <!-- 购物车 的商品计算 -->
                        <CartControl :food='food'/>
                  </div>
                </div>
              </li>
            </ul>
          </li>
        </ul>
      </div>
      <!-- 购物车结算组件 -->
      <!-- <ShopCart></ShopCart> -->
    </div>
    <!-- <Food :food="showMyfood" ref="food"/> -->
    <!-- 1 父组件向子组件传递值 props 接受 -->
    <!--  2 子组件向父组件传递值（传递的一个方法）$emit -->
    <!-- 3  父组件调用子组件的方法 -->
  </div>
</template>

<script>
import {mapState} from 'vuex'
import CartControl from '../../../components/CartControl/CartControl'

// 使用 better-scroll
import BScroll from 'better-scroll'
export default {
    data() {
        return {
                supportClasses: ['activity-green', 'activity-red', 'activity-orange'],
                supportsShow: false,
                shopShow: false,
                // currentIndex:0,  //左边导航栏高亮
                tops:[] ,        // 包含右侧所有分类小列表的top 值
                scrollY:'',      //右侧Y 轴滑动的坐标
        };
    },
//   @@ -16,14 +87,113 @@ export default {

//     },
    mounted() {
      this.$store.dispatch('getShopGoods',()=>{
          this.$nextTick(()=>{ /* 延迟下一次dom更新 立即调用 */

              this._initScroll()
              this._initTops()
          })
      })  

    },
    components:{
        CartControl
    },
    methods: {
            clickMenuItem(index){
                // this.currentIndex=index
                let tops=this.tops[index]
                this.scrollY=tops
                // 平滑滚动到指定位置  滚动到某一个位置
                this.foodsScroll.scrollTo(0,-tops,300)
            },


            // 初始化滚动
            _initScroll() {
                  // new  BScroll('第一个参数是一个dom选择器','第二个参数是配置对象')
             
              //方式一
            // let  menuWrapper=this.$refs.menu-wrapper
            
            // new  BScroll(menuWrapper)
             //方式二 
             new BScroll('.menu-wrapper',{
               click:true
             })

             // BScroll 触发滚动事件 
           this.foodsScroll=  new  BScroll('.foods-wrapper',{
                 click:true,
                 probeType: 2, // 手指滑动(惯性滑动和编码滑动不监视) (1,2,3)
             })

          //实时监听滚动的事件 
          this.foodsScroll.on('scroll',(pos)=>{
            // console.log('on sroll')
            // console.log(pos)
            this.scrollY = Math.abs(pos.y)
          })
          // 监听滚动结束事件  获取 滚动结束停止的时候y的值
          this.foodsScroll.on('scrollEnd',(pos)=>{
            console.log('scrollEnd')
            console.log(pos)
             this.scrollY = Math.abs(pos.y)
          })

            },


             _initTops() {
        let top=0;
        let myTops=[];
        //第一个li不需要滚动
        myTops.push(top)


        //1 获取右边所有的li标签
      let foodsUl_lis=  this.$refs.foodsUl.getElementsByClassName('food-list-hook')
       console.log(foodsUl_lis)
        //2 获取右边所有的li标签滚出去的高度
         Array.from(foodsUl_lis).forEach((li,index)=>{
           top+=li.clientHeight
           myTops.push(top)
         })

         console.log(myTops)

         this.tops=myTops

        //3 同步左边导航栏高亮 

      }



             
    },
    computed:{
        ...mapState(['goods']),

            currentIndex(){  //计算属性
                let {tops,scrollY}=this 
                let current=tops.findIndex((item,index)=>{
                    return scrollY>= tops[index] &&scrollY< tops[index+1]
                })
                return current
            }

    }
};
</script>

<style lang="stylus" rel="stylesheet/stylus">
  @import "../../../common/mixins"
  .goods
    display: flex
    position: absolute
    top: 215px
    bottom: 46px
    width: 100%
    background: #fff;
    overflow: hidden
    .menu-wrapper
      flex: 0 0 80px
      width: 80px
      background: #f3f5f7
      .menu-item
        display: table
        height: 54px
        width: 56px
        padding: 0 12px
        line-height: 14px
        &.current
          position: relative
          z-index: 10
          margin-top: -1px
          background: #fff
          color: $green
          font-weight: 700
          .text
            border-none()
        .icon
          display: inline-block
          vertical-align: top
          width: 12px
          height: 12px
          margin-right: 2px
          background-size: 12px 12px
          background-repeat: no-repeat
        .text
          display: table-cell
          width: 56px
          vertical-align: middle
          bottom-border-1px(rgba(7, 17, 27, 0.1))
          font-size: 12px
    .foods-wrapper
      flex: 1
      .title
        padding-left: 14px
        height: 26px
        line-height: 26px
        border-left: 2px solid #d9dde1
        font-size: 12px
        color: rgb(147, 153, 159)
        background: #f3f5f7
      .food-item
        display: flex
        margin: 18px
        padding-bottom: 18px
        bottom-border-1px(rgba(7, 17, 27, 0.1))
        &:last-child
          border-none()
          margin-bottom: 0
        .icon
          flex: 0 0 57px
          margin-right: 10px
        .content
          flex: 1
          .name
            margin: 2px 0 8px 0
            height: 14px
            line-height: 14px
            font-size: 14px
            color: rgb(7, 17, 27)
          .desc, .extra
            line-height: 10px
            font-size: 10px
            color: rgb(147, 153, 159)
          .desc
            line-height: 12px
            margin-bottom: 8px
          .extra
            .count
              margin-right: 12px
          .price
            font-weight: 700
            line-height: 24px
            .now
              margin-right: 8px
              font-size: 14px
              color: rgb(240, 20, 20)
            .old
              text-decoration: line-through
              font-size: 10px
              color: rgb(147, 153, 159)
          .cartcontrol-wrapper
            position: absolute
            right: 0
            bottom: 12px
</style>
